A COMPARISON OF Microbacterium thermosphactum AND LACTOBACILLI AS SPOILAGE ORGANISMS OF VACUUM‐PACKAGED SLICED LUNCHEON MEATS

The spoilage of vacuum‐packaged sliced luncheon meats at 5°C by Microbacterium thermosphactum and lactobacilli was studied using analytical taste panels. M. thermosphactum caused rapid spoilage. “Off” aroma was significant at about the time the bacterial population reached 10 8 /g and “off” flavor 2–3 days later. In contrast homofermentative lactobacilli caused spoilage much more slowly. No “off” aroma was detected with products which had carried a population of 10 8 /e. for 21 days the time at which “off” flavor first became significant. Heterofermentative lactobacilli were intermediate in their effect. Thus shelf life is dependent upon the types of bacteria present. Under such circumstances a “total count” microbiological standard is of little value.